It's strange. It seems that Samuel French took Elegies off of the site. Although they did have the rights, even a month ago (I emailed them about obtaining a perusal). If you have to obtain the rights from William Finn himself, does anyone know how to go about doing that?
Sam French does own the rights to Elegies, as well as almost all of William Finn's shows. You should call the musical dept. at (212) 206-8125 and find out why it's not listed. Mr. Finn could be revising it, or a major production is doing it which will cancel out stock productions, but I would call them directly and find out why it isn't being offered. Hope that helps.